FIG. 10 shows an outlined construction of a usual prior art mode switching transmitting mechanism. In the same figure, in order to facilitate understanding relation to the construction of the present invention, various corresponding parts are indicated by the same reference numerals as those used in figures representing an embodiment of the present invention.
In FIG. 10, 18a and 18b are a right and a left reel gears, respectively; 27 and 32 are coaxial driving gears, whose shaft is indicated by 30a; 22 and 22a are coaxial driven gears; and 20 is an idle gear. The gear 22 having a greater diameter and the gear 22a having a smaller diameter described above are supported rotatably by a pivoting arm (not indicated in the figure) and pivoted around the shaft 30a. The reel gears 18a and 18b as well as the idle gear 20 are supported rotatably at fixed positions.
At switching the different modes, that is, tape fast forward (FF) and rewinding (REW) or play (FWD) and play (RVS), the gear 22 is engaged with either one of the reel gear 18a and the idle gear 20 by pivoting displacement of the pivoting arm. Since the modes FF and REW or FWD and RVS are switched by pivoting displacement of the gear 22, as described above, it is necessary to dispose the idle gear for either one of the reel gears.
Further, in connection with an intrusion angle of gears, the pivotably displaced gear 22 is disposed at a position protruding upward from a line connecting the centers of the reel gears 18a and 18b. Owing to this construction it is possible to obtain advantages that the intruding force of the gear 22 is relatively small, that there is no risk to rotate the gear 22, when the gear 22 is disengaged from the idle gear 20, because the contact angle .beta. to the gear 22 is small (an angle around 70.degree. is desirable), and that a small operating force is sufficient, etc.
However, when the mechanism is so constructed that the gear 22 protrudes upward from the line connecting the centers of reel gears 18a and 18b, there are problems that, in a small size tape player, negatively affect space factor as a result, space for accommodating a battery can be taken up, etc.
Therefore, in order to remove the disadvantages on the space described above, another construction, wherein the gear 22 is disposed on the line connecting the centers of the reel gears, as indicated in FIG. 11, is conceivable. However, in this construction, since the contact angle .beta. of the gear 22 with respect to the gear 20 is great (greater than 90.degree.), when the gear 22 is disengaged from the gear 20, it rotates more or less the gear 20, and in particular, when the gear 22 is disengaged at the end of the tape, an extremely great force is required. For this reason, lever operation is very heavy.
As the gear switching mechanism described above, there are known heretofore a mechanism, so constructed that the gear is switched through a rotating member linked with sliding of a head plate supporting a head, or having such construction that the gear is switched by thrusting it directly by means of an FF/REW lever, but in the former mechanism larger parts should be used, which requires a large space and on the contrary, in the latter mechanism, the number of parts is increased, which gives rise to higher costs.